Description
Gamma Ray Bursts (GRBs) can be used to address key scientific questions on the formation of the Universe including: When did the star formation begin and how did it evolve? When and how did the intergalactic medium become re-ionized? What processes governed its early chemical enrichment? Long GRBs signal when a massive star collapses and provide a tracer of massive star formation. The GRB afterglow is a bright beacon lasting a few days that can be used out to the highest redshifts to probe the intervening material from the host galaxy and intergalactic medium. The Gamow Explorer will detect and locate GRBs from the z > 6 high redshift universe. A wide field X-ray telescope detects GRBs and triggers a rapidly slewing spacecraft to point an Infra-red telescope to obtain an arc second location and autonomously determine whether the redshift is greater than 6. For z>6 GRBs a redshift alert will enable follow up by large telescopes. The Gamow Explorer will be proposed to the 2021 NASA MIDEX opportunity, for launch in 2028. It will be a key component in the multi-messenger era of JWST, 30-m class telescopes and gravitational wave detectors.